Device-to-Device (D2D) communication is a new technology of allowing communication by multiplexing intra-cell resources directly between User Equipments (UEs) under the control of a cellular system. The benefits brought by the technology includes: relieving load of the cellular network, reducing battery consumption of the UE, using radio resources more effectively, and achieving a larger signal coverage area and lower system interference level and so on. Moreover, the problem of wireless communication spectrum resource scarcity can be solved to a certain degree. Therefore, in recent years, the D2D technology has become a very promising new concept and got more and more extensive attention.
The carrier aggregation (CA) technology is introduced into a Long-Term Evolution Advance (LTE-A) standard since dispersed frequency spectrums can be grouped into large bandwidth with the carrier aggregation technology to satisfy the requirements of the future peak rate, and cell resources can be flexibly configured with the carrier aggregation technology, which maximally utilizes idle frequency spectrums. However, if the load of the cellular network is heavy, it is hard to find idle resources for the carrier aggregation. If the above two technologies can be integrated, that is, using the D2D technology in the carrier aggregation, on the one hand, cell resources can be configured conveniently and flexibly, and a utilization rate of the frequency spectrum can be increased; on the other hand, by utilizing high-quality D2D links and multiplexing cell resources, the transmission efficiency of the traditional cellular network can be further improved greatly, and the peak rate can also be enhanced for the users in the meantime. For example, when certain two users close to each other need to download the same large data (e.g. a song or a film), in the traditional method, each user needs to receive the complete data file via a cellular downlink of the user, but if it is to consider combining the carrier aggregation and the D2D, for example, a base station divides a datum B required to be transmitted into three component data blocks B1, B2 and B3 (B=B1+B2+B3) and transmits the component data blocks B1, B2 and B3 respectively to users, and each user performs data sharing via a D2D link in the meantime, on the one hand, the load of the cellular communication network is reduced, on the other hand, the transmission efficiency of the cellular network is also greatly enhanced.
With respect to the above problems in the related art, no effective solution has been proposed so far.